Most digital cameras today are similar in size to and behave like conventional point-and-shoot cameras. Unlike conventional cameras, however, most digital cameras store digital images in an internal flash memory or on external memory cards, and some are equipped with a liquid-crystal display (LCD) screen on the back of the camera. Through the use of the LCD, most digital cameras operate in two modes, record and play, although some only have a record mode. In record mode, the LCD is used as a viewfinder in which the user may view an object or scene before taking a picture. In play mode, the LCD is used as a playback screen for allowing the user to review previously captured images either individually or in arrays of four, nine, or sixteen images.
Digital camera user interfaces typically include a number of buttons or switches for setting the camera into one of the two modes and for navigating between images in play mode. One type of camera, for instance, includes two navigation buttons labeled "-" and "+", a mode button, a display button, a zoom button and a delete button. Play mode for this camera begins with a default screen displaying a full-sized individual image. Other images stored in the camera may then be displayed in a backward or forward sequence by pressing the "-" and "+" navigation buttons, respectively. Pressing the mode button during play mode causes four images to be displayed in a 2.times.2 array, and pressing the mode button again causes nine images to be displayed in a 3.times.3 array. The user can then "page" through screens of image arrays by pressing the navigation buttons, or the user can move from image to image in the arrays by first pressing the display button and then traversing across the images in the rows of the arrays using the navigation buttons. The user may have the full-sized image displayed of a chosen image by pressing the zoom button or can delete the image by pressing the delete button.
Digital cameras typically have a play mode in which a user can view a full-size image of a scene which has been previously captured. The user may choose to continuously view several images. It can be a nuisance, however, when some of the images are in landscape format, while other images are in portrait format. If the user is viewing several images one after another, the user must rotate the digital camera every time a landscape image appears after a portrait image, and vice versa.
What is needed is a method and apparatus for automatically rotating the images to a consistent format to avoid the user having to frequently rotate the camera. The present invention addresses such a need.